Hotz announced the news on the Comma.ai official Twitter account, noting that the decision to cancel was made after he received a letter from the National Highway and Traffic Safety Administration (NHTSA). The NHTSA letter explained that given its mandate of ensuring safety on U.S. roadways, it needed to ensure the Comma One is compliant with regulations before it can be offered for sale.

NHTSA then issued a “special order” directed at Comma.ai, which insisted that the company provide detailed answers to 15 questions related to Comma One, its design, testing practices and information regarding safety trials, intended target vehicles and anticipated sales timeline. These appear to be fairly standard requirements for a device that purports to be able to take over operation of your car, even if only in limited circumstances.

Hotz tweeted from the official Comma.ai account that rather than providing the requisite response, the company would instead be cancelling Comma One entirely, and turning its attention to “other products and markets,” since Hotz says that the prospect of a life “dealing with regulators and lawyers… isn’t worth it.” Hotz noted that he was tweeting from Shenzhen, China, which could suggest he was in the process of working on some aspect of Comma One’s production.

The Comma One was unveiled for the first time at TechCrunch Disrupt SF this past September, when Hotz presented the product and announced that it would be shipping to early customers by the end of this year. On stage, I asked Hotz about safety issues and concerns, but he expressed confidence that Comma One wasn’t doing anything existing technology on the market doesn’t already offer.

Hotz had criticized competitors for not being able to actually ship autonomous or driver-assistance features on stage, and also detailed a series of exchanges between himself and Tesla CEO Elon Musk around a potential job offer for Hotz at the electric car company.

We’ve reached out to Hotz for more info on the Comma One cancellation and what kind of alternative products and markets Comma.ai is looking at next, but had not received a response in time for publication. The full NHTSA letter received by Comma.ai is embedded below.